Gold Revisited

Psalm 119:72
The law of thy mouth is better unto me than thousands of gold and silver.

Gold must be one of the most remarkable elements in the Periodic Table. Its chemical symbol is Au, its atomic number is 79, and its atomic mass is 196.967. It is a lustrous, yellow-colored metal, and is almost chemically inert. It is this lack of chemistry, coupled with its rarity, that gives it its value.

Image: Cube of goldGold is almost completely unreactive to the sort of agents that normally corrode metals, such as water or acids. It will, however, react with aqua regia – a blend of nitric and hydrochloric acids. Because of this unreactivity, gold is found as a native metal, not as a compound or ore. Most gold that is mined is stored as bullion, but its attractiveness and monetary value make it useful in jewelry.

Because gold has such a large atom, it has a great many electron orbitals. The outer orbitals are very large for atoms, so an electron in the 5d orbital can reach speeds approaching the speed of light. The transition of an electron from the 5d to 6s orbital requires a photon of energy. However, by analogy with the transition from 4d to 5s in silver, this ought not to alter the basic silver color of the metal. But the speed of the 5d orbital is such that there is a relativistic effect, causing this transition to absorb a photon in the blue range of the visible spectrum. With blue light thus absorbed, gold appears, well, gold-colored! I find it fascinating that, when looking at my gold wedding ring, I am seeing Einstein’s theory of relativity in action.

Gold is a metal fit for a king. That is why the Wise Men brought some to the child Jesus.

Prayer: Thank You for making materials as beautiful as gold. When we learn more about its properties, we stand amazed at Your Creative Power. Amen.

Author: Paul F. Taylor

Ref: Royal Society of Chemistry, Periodic Table, , accessed 7/28/2017. Image: Toi Mine, Creative Commons Attribution-Share Alike 3.0 Unported